Continuous beam result
12.0 × 24.0 in
3-#8
f′c 4000 psi
fy 60.0 ksi
d 21.62 in
2 spans
PASS
All 4 critical sections pass: flexure, shear, crack control, deflection.
Input summary
| Span | L (ft) | wD (klf) | wL (klf) |
|---|---|---|---|
| Span 1 | 20.0 | 1.5 | 1.0 |
| Span 2 | 20.0 | 1.5 | 1.0 |
Supports: pin (left), pin (right); interior: continuous (pinned)
Moment and shear envelopes
Pattern loading skipped (L/D ≤ 0.75 per ACI 6.4.3): single full-load case analyzed.
Critical sections
| Location | Mu (kip-ft) | Vu (kip) | Type | Status |
|---|---|---|---|---|
| Span 1 midspan | 109.5 | 1.7 | rectangular | PASS |
| Span 1 right support | 170.0 | 36.4 | rectangular | PASS |
| Span 2 midspan | 109.5 | 1.7 | rectangular | PASS |
| Span 2 left support | 170.0 | 36.4 | rectangular | PASS |
Span 1 midspan PASS
Section type: rectangular (positive moment, flange in compression)
D/C moment
0.52
- φMn (kip-ft)
- 212.0
- Mu (kip-ft)
- 109.5
D/C shear
0.04
- φVn (kip)
- 46.0
- Vu (kip)
- 1.7
Crack control:
PASS
Span 1 right support PASS
Section type: rectangular (negative moment, rectangular)
D/C moment
0.80
- φMn (kip-ft)
- 212.0
- Mu (kip-ft)
- 170.0
D/C shear
0.79
- φVn (kip)
- 46.0
- Vu (kip)
- 36.4
Crack control:
PASS
Span 2 midspan PASS
Section type: rectangular (positive moment, flange in compression)
D/C moment
0.52
- φMn (kip-ft)
- 212.0
- Mu (kip-ft)
- 109.5
D/C shear
0.04
- φVn (kip)
- 46.0
- Vu (kip)
- 1.7
Crack control:
PASS
Span 2 left support PASS
Section type: rectangular (negative moment, rectangular)
D/C moment
0.80
- φMn (kip-ft)
- 212.0
- Mu (kip-ft)
- 170.0
D/C shear
0.79
- φVn (kip)
- 46.0
- Vu (kip)
- 36.4
Crack control:
PASS
Deflection
PASS| Span | Ie,avg (in4) | δD (in) | δL (in) | δLT (in) | L/δ | Status |
|---|---|---|---|---|---|---|
| span_1 | 7370 | 0.084 | 0.056 | 0.225 | 1067 | PASS |
| span_2 | 7370 | 0.084 | 0.056 | 0.225 | 1067 | PASS |
Weighted-average Ie per ACI 435.3R-68 (0.70·Ie,mid + 0.15·(Ie,left + Ie,right)); Bischoff Ie per ACI 24.2.3.5.
Calculated 2026-10-25 · ACI 318-19